Bradford Factor Calculator
Calculate the Bradford Factor, an HR metric that weights frequent short absences more heavily than occasional long ones. Enter the number of separate absence spells and the total days absent to get the score.
Formula
Bradford Factor = (Absence Spells)² × Total Days Absent
- The score squares the number of separate absence spells, so frequent short absences score far higher than a single long one.
- For example, the same 10 days off scores 10 as one spell but 1000 as ten separate one-day spells.
- A 'spell' is a single continuous period of absence, regardless of how many days it lasts.
- Many employers set trigger thresholds (often around 100–500) at which a formal attendance review begins.
4 spells totalling 12 days
Inputs
- Number of Absence Spells: 4 spells
- Total Days Absent: 12 days
Bradford Factor = 4² × 12 = 16 × 12 = 192. The same 12 days taken as one spell would score only 12.
Frequently asked questions
What is the Bradford Factor?
It's an HR formula that scores employee absence, deliberately penalising frequent short absences more than occasional long ones because they are more disruptive.
Why are short absences weighted more heavily?
Because the number of spells is squared. Repeated unplanned days off are harder to cover than a single planned long absence of the same total length.
What counts as a spell?
A spell is one continuous period of absence. Five separate one-day absences are five spells; one five-day absence is a single spell.
What is a high Bradford Factor?
It depends on each employer's policy, but scores in the hundreds typically trigger an attendance review. There is no universal cut-off.